[elblako91]

Hey everyone, just got back from vacation. I'm not all emo anymore and my heads up high. All i needed was a break from the nova. I was anxious to tear it apart. Got home today around 12 and i got right to work. Finished around 6ish. Anyways here are some pictures. Looks like i need some new pistons and lord knows what else. I just can not believe improper break in did this. Learned my lesson the hard way and learned it GOOD! :yes: but time to move on.

 

[Rroxon7]

I'm glad you not ready to hang it up....Do all the nessasary research, take your time, ask all the questions you need, or find important...The next time you fire it up...Don't worry so much about timing and the little things.....get water...leave the radiator cap off...get an extra fan, the bigger the better...watch your tach, temp..And time..Get a clock or watch ..Let it run for 20-30 min. at 2000-2200..And all will be fine...Hope you enjoyed your vacation...Now its time to get on it.........Good luck....

 

[elblako91]

I'm going to give the engine shop a call tomorrow and see if there is any chance he will swap it out for another rebuilt long block and if not can anyone recommend some pistons? I've never messed with internals before.

-Budget is 800 (give or take)
-I want to keep the heads stock
-Maybe a different cam then the one I've been using which is THIS grind.
-I want to increase compression ratio
-This will be a daily driver so it will rarely see anything over 5000 rpm's

Thanks fellas

 

[levisnteeshirt]

why stock heads ??

dern , look at a set of these , if you got the money ,,, a 406 with vortecs and a small cam ur over 420 + HP , near 500 ftlbs of torque

http://www.jegs.com/p/Patriot-Perfo...-Vortec-185cc-Cylinder-Heads/1192214/10002/-1

use these with a dish piston , you'd be amazed at the difference

But i'd take it back ,,, if he's a decent guy, he doesn't want it known one of his engines did that ,,,

 

[Paul Wright]

If you broke a piston that bad you may have broke the block when the loose rod punched the cylinder. If the engine's been over bored you won't have a lot of meat left to go bigger safely.

 

[6NOVA4]

keep tearing it down and take lots of pics. Did you call the machine shop you got the engine from? curious as to the root cause of piston failure. Hopefully they don't pull the " well you took it apart so the warranty is void" crap. PICS!!!!

 

[elblako91]

I was going to take more pictures but my camera died. Heads are kind of out of my price range. Hopefully no damage was done do the block as I'm pretty sure it has been bored over since it is rebuilt. Im going to take this one slow and start the tear down tomorrow.

 

[heavy7DchevY]

How in god's name would improper break in cause a piston to break like that?

 

[elblako91]

How in god's name would improper break in cause a piston to break like that?

Ha yeah me and my dad said the same thing.

 

[74 hatchback]

I heard of hypertectic pistons blowing up due to to much silicone in the metal making them weak. Is that what they are? thats the only reason i can think of, good luck.

 

[64Chevy2]

Is that the skirt of the piston or the top?

 

[elblako91]

Not sure yet. I can tell you more tomorrow when i rip it apart.

 

[6NOVA4]

I also heard and this happened to a friend of mine that with hyper-u-cracked it pistons you have to run bigger ring gaps than forged or cast pistons. If not....(insert noise for bomb exploding):devil:

 

[patman]

How in god's name would improper break in cause a piston to break like that?

you have to run bigger ring gaps than forged or cast pistons. If not....(insert noise for bomb exploding):devil:

I'm no expert, but... I'd think the worst thing that can happen with improper breakin (at least in the 20 minute timeframe you ran yours) is wiped cam lobes and toasting the rod/main bearings/journals from the resulting filings. What you've got there is piston chunks.

Ring gaps too tight? Valve hitting the piston? Valve lash too tight? I'd call the builder...

 

[bowtie0069]

I heard of hypertectic pistons blowing up due to to much silicone in the metal making them weak.

Nonsense, there's nothing wrong with hypereutectic pistons. They are quite strong, but don't "give" like a forging--if you detonate them they can shatter, but it takes some pretty serious rattling to hurt them. KB's do require larger gaps (or you end with broken parts) Some like Speed-Pro's can be installed with conventional gaps. One of my 391's with 13.5-1 KB's ran 10.20's--I used .039" gaps.
That doesn't look like it had anything to do with improper break-in. Was there any evidence of piston to valve contact? Are those KB pistons?? (on the bottom they will have KB or Silvolite cast in)

 

[Ryan V64SS]

I had a set of KB hypereutectic's in my street/strip motor for 12 years, when I tore the motor down they still looked almost brand new! I actually sold them on e-bay for $80.:yes:

 

[D-Man]

Just curious...but.....that almost looks like improper piston-to-bore clearance or a problem with the bore having too much taper or out of round. I'd bet those are most of the piston skirts.:yes:

Definitely nothing to do with the break-in process!!!!:no:

 

[elblako91]

Well me and my dad found it best not to call them but to just show up and see what they said. I'll let everyone know what happened by tonight.

 

[boyds67wagon]

Well me and my dad found it best not to call them but to just show up and see what they said. I'll let everyone know what happened by tonight.

I can't see this being caused by the incorrect break in either. My vote goes with the previously stated bore issue.

 

[D-Man]

Well me and my dad found it best not to call them but to just show up and see what they said. I'll let everyone know what happened by tonight.

Ask them the hard questions before they start looking at anything. Bore clearance? Amount of allowable taper? Ring gap?
THEN get them to do some measuring right in front of you!! It's kinda hard to argue the numbers!!

What might get REAL interesting is if they claim not to have a dial bore gauge to accurately measure the bores. Or if they refuse to do any measuring in FRONT of you and just want to take it in the back for their guy to "Check it out".

Good luck!!!